DOWNEY -- One by one, Rancho Los Amigos patients, their families and staff eagerly lined up, ready to scream. Covered with tombstones, spider webs and ghoulish monsters, a simple storage room, with the help of Knott's Berry Farm, was transformed yesterday into the scariest haunted house the rehabilitation center has seen to date. "Rancho does Halloween big," said Lilli Thompson, chief of physical therapy. "This is very special for our patients - we want them to feel like they can still participate in Halloween. It's therapeutic." Hosted annually by Rancho's therapy staff, the haunted house tradition gives patients the opportunity to enjoy Halloween festivities at the center where many receive treatment for various debilitating injuries. "It's recreation," said Cheryl Guinn, public information officer at Rancho. "Many of our patients are here for months and weeks at a time - they don't get a chance to go out. This is something that can provide them some therapy and fun." This year marked some change for the annual event as Knott's Berry Farm partnered with Rancho Los Amigos to enhance the Halloween experience for its patients. Knott's Berry Farm, which transforms into Knott's Scary Farm during the Halloween season, donated several props to Rancho and sent creepy monsters to help recreate the park's chilling atmosphere. The monsters arrived to the center in a black hearse, parading their way into the haunted house, inciting loud screams and giddy laughs from patients and staff members. Magician Craig Childrass, 23, works at Knott's, entertaining crowds with his tricks and illusions, but yesterday, the Seal Beach resident spent time performing for patients waiting in line. "Many of them have never seen these tricks," Childrass said. "It's great when they see the magic happen in their own hands." For Rancho CEO Jorge Orozco, the haunted house was a success if it provided one thing. "Normalcy," Orozco said. "When you're injured you think there's no tomorrow. But we're showing them that when they leave here, they will celebrate holidays. This is a great distraction for our patients."